3 resultados para Southeast Asia -- Description and travel

em DigitalCommons@University of Nebraska - Lincoln


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Aim To assess the distribution, group size, seasonal occurrence and annual trends of cetaceans. Location The study area included all major inland waters of Southeast Alaska. Methods Between 1991 and 2007, cetacean surveys were conducted by observers who kept a constant watch when the vessel was underway and recorded all cetaceans encountered. For each species, we examined distributional patterns, group size, seasonal occurrence and annual trends. Analysis of variance (anova F) was used to test for differences in group sizes between multiple means, and Student’s t-test was used to detect differences between pairwise means. Cetacean seasonal occurrence and annual trends were investigated using a generalized linear model framework. Results Humpback whales (Megaptera novaeangliae) were seen throughout the region, with numbers lowest in spring and highest in the fall. Fin whale (Balaenoptera physalus) and minke whale (Balaenoptera acutorostrata) distributions were more restricted than that reported for humpback whales, and the low number of sightings precluded evaluating seasonal trends. Three killer whale (Orcinus orca) eco-types were documented with distributions occurring throughout inland waters. Seasonal patterns were not detected or could not be evaluated for resident and offshore killer whales, respectively; however, the transient eco-type was more abundant in the summer. Dall’s porpoise (Phocoenoides dalli) were distributed throughout the region, with more sightings in spring and summer than in fall. Harbour porpoise (Phocoena phocoena) distribution was clumped, with concentrations occurring in the Icy Strait/Glacier Bay and Wrangell areas and with no evidence of seasonality. Pacific white-sided dolphins (Lagenorhynchus obliquidens) were observed only occasionally, with more sightings in the spring. For most species, group size varied on both an annual and seasonal basis. Main conclusions Seven cetacean species occupy the inland waters of Southeast Alaska, with distribution, group size, seasonal occurrence and annual trends varying by species. Future studies that compare spatial and temporal patterns with other features (e.g. oceanography, prey resources) may help in identifying the key factors that support the high density and biodiversity of cetaceans found in this region. An increased understanding of the region’s marine ecology is an essential step towards ensuring the long-term conservation of cetaceans in Southeast Alaska.

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The transport of anthropogenic and natural contaminants to public-supply wells was evaluated in a part of the High Plains aquifer near York, Nebraska, as part of the U.S. Geological Survey National Water-Quality Assessment Program. The aquifer in the Eastern High Plains regional study area is composed of Quaternary alluvial deposits typical of the High Plains aquifer in eastern Nebraska and Kansas, is an important water source for agricultural irrigation and public water supply, and is susceptible and vulnerable to contamination. A six-layer, steady-state ground-water flow model of the High Plains aquifer near York, Nebraska, was constructed and calibrated to average conditions for the time period from 1997 to 2001. The calibrated model and advective particle-tracking simulations were used to compute areas contributing recharge and travel times from recharge areas to selected public-supply wells. Model results indicate recharge from agricultural irrigation return flow and precipitation (about 89 percent of inflow) provides most of the ground-water inflow, whereas the majority of ground-water discharge is to pumping wells (about 78 percent of outflow). Particle-tracking results indicate areas contributing recharge to public-supply wells extend northwest because of the natural ground-water gradient from the northwest to the southeast across the study area. Particle-tracking simulations indicate most ground-water travel times from areas contributing recharge range from 20 to more than 100 years but that some ground water, especially that in the lower confined unit, originates at the upgradient model boundary instead of at the water table in the study area and has travel times of thousands of years.

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A comprehensive revision of the Subfamily Parandrinae (Coleoptera, Cerambycidae) from the Hawaiian, Australasian, Oriental, and Japanese regions is presented. Seven (7) new genera are described: Komiyandra, Melanesiandra, Papuandra, Storeyandra, Hawaiiandra, Caledonandra, and Malukandra. All known, indigenous species from these regions are assigned to new genera resulting in the following new combinations: Komiyandra janus (Bates, 1875), K. shibatai (Hayashi, 1963), K. formosana (Miwa and Mitono, 1939), K. lanyuana (Hayashi, 1981), Melanesiandra striatifrons (Fairmaire, 1879), M. solomonensis (Arigony, 1983), Caledonandra austrocaledonica (Montrouzier, 1861), C. passandroides (Thomson, 1867), Hawaiiandra puncticeps (Sharp, 1878), Malukandra heterostyla (Lameere, 1902), Storeyandra frenchi (Blackburn, 1895), and Papuandra araucariae (Gressitt, 1959). Thirty-one (31) new species are described: Komiyandra javana, K. nayani, K. ohbayashii, K. luzonica, K. philippinensis, K. mindanao, K. mehli, K. vivesi, K. lombokia, K. sulawesiana, K. irianjayana, K. menieri, K. sangihe, K. mindoro, K. niisatoi, K. drumonti, K. cabigasi, K. koni, K. johkii, K. poggii, K. uenoi, Melanesiandra bougainvillensis, M. birai, Papuandra gressitti, P. weigeli, P. queenslandensis, P. norfolkensis, P. rothschildi, P. oberthueri, Malukandra jayawijayana and M. hornabrooki. A lectotype is designated for Parandra janus Bates, 1875. Komiyandra janus (Bates, 1875) is excluded from nearly all previously reported locations, even one location given in the original description, and is now only known from Sulawesi. A paralectotype of Parandra janus Bates, 1875, is designated as a paratype for Komiyandra menieri, new species. Komiyandra formosana is excluded from the Japanese (Ryukyu Is.) fauna. Parandra vitiensis Nonfried, 1894, is again placed in synonymy with P. striatifrons Fairmaire (now Melanesiandra striatifrons). A neotype is designated for Parandra austrocaledonica Montrouzier, 1861. A lectotype is designated for Parandra janus Bates, 1875. The lectotype of Parandra gabonica Thomson, 1858, designated by Quentin and Villiers (1975) is considered invalid. Papuandra araucariae (Gressitt, 1959) is excluded from the fauna of Norfolk Island. The African species Stenandra kolbei (Lameere, 1903) is reported for the first time from Asia (N. Vietnam). Keys are presented to separate worldwide genera of Parandrini and all species within the study regions. Illustrations are provided for all species including many special characters to differentiate genera and species.